Recently, a semiconductor apparatus is known in which metal plates are electrically and thermally connected to upper and lower surfaces of a plurality of semiconductor elements and are sealed by a sealing resin (see Japanese Laid-open Patent Publication No. 2012-235081, for example). An example of such a semiconductor apparatus includes semiconductor elements such as Insulated Gate Bipolar Transistors (IGBTs), diodes, etc., arranged side by side in lateral and longitudinal directions.
The IGBT corresponds to a transistor that is formed by replacing a base of a bipolar transistor with a gate of a field-effect transistor (FET), and has high speed and withstand electric power characteristics of the bipolar transistor that is of a current-driven type as well as electric power saving characteristics of the field-effect transistor that is of a voltage-driven type. Thus, the semiconductor apparatus as described above can be used as a power semiconductor apparatus that performs switching operations.
With respect to such a semiconductor apparatus as described above, a concave portion may be provided in a resin portion for reserving a creepage distance. However, there may be a case where heat generated by the semiconductor elements causes a stress concentration at the concave portion.
Therefore, an object of this disclosure is to provide a semiconductor apparatus that can reduce a stress concentration at a concave portion that is provided for increasing a creepage distance.